Sound restricting door seal



Dec. 7, 1965 D. c. SMELTZER 3,221,376

SOUND RESTRICTING DOOR SEAL Filed June 7. 1963 P113: 1. w P15- 3- E INVENTOR.

DONALD 6. SMEL TZER Attorneys United States Patent 3,221,376 SOUND RESTRICTING DOOR SEAL Donald C. Smeltzer, Greensburg, Pa., assigmor to Overly Manufacturing Company, Greensburg, Pa., a corporation of Pennsylvania Filed June 7, 1963, Ser. No. 286,234 2 Claims. (CI. 20-69) The present invention relates to sound attenuating doors as employed in commercial, residential, public, hospitals and other types of buildings where passage of sound through the doors, particularly in the range of conversation and business machine noises, are objectionable. More specifically, the invention pertains to a novel form of seal disposed upon the door frame about the entire periphery of the door panel to reduce or exclude passage of air borne sound through the clearance spacing between the periphery of the door panel and the adjacent faces of the door mounting frame.

customarily about 1 inch clearance is provided between the vertical edge of the panel and the adjacent face of the door frame at the hinge side of the door, and upwards to inch clearance between the horizontal top and bottom edges of the door panel and the adjacent frame face. In some cases the vertical door panel face containing the door lock may have a greater clearance with the frame due to the frame face being flat and the adjacent panel edge being inclined as shown.

One object of the invention is to provide a door seal of the character described which inhibits passage of air borne sound at the clearance openings between the door panel and frame.

Another object of the invention is to provide a door seal having the function of relief of sound pressure at the spaced areas and absorption to prevent transmission through said spaced areas.

These and other objects of the invention will be made apparent from the following description and the drawing forming a part thereof, wherein:

FIG. 1 shows in elevation the door panel and door frame within which the panel is mounted for pivotal movement towards and away from the supporting frame;

FIG. 2 shows a transverse section through the panel, frame and sound seal taken on lines II--Il;

FIG. 3 shows a vertical section through the panel frame and door seal taken on lines III-III, showing one form of seal member;

FIG. 4 shows a transverse section through one form of the sound seal member; and

FIG. 5 shows a transverse section through a preferred form of sound seal member.

The door panel, per se, forms no part of the present invention. It should, of course, provide a maximum sound transmission loss and may be of any suitable construction and thickness. Reference is made to the copending application of Herbert W. Wehe, Ir., Serial No. 286,289, filed June 7, 1963 showing a plurality of forms of door panel construction providing large sound transmission losses for various sound frequencies impinging upon either face thereof.

Referring now to FIGS. 1 through 3 of the drawing, the door panel 1 at one side thereof, is pivotally attached by hinges 2 to one side of door frame 3. At the opposite side of the door frame the door panel and frame is provided with a customary latching mechanism not shown. The door frame, as shown in FIGS. 2 and 3, comprises suitable generally channel-shaped top and side members 4 having their webs 5 disposed in opposing relation to the adjacent marginal edges of the door panel and a suitable bottom memberfi of generally channel-shape having its web 7 disposed in opposing relation to the adjacent transverse bottom marginal edge of the door panel.

r 3,221,375 Patented Dec. 7, 1965 At the hinge side of the door panel, the frame channel 4 has the web thereof reinforced by a suitable hinge butt reinforcing member 8 at each hinge and the door panel has a similar reinforcement (not shown) to which the hinge leafs are attached for mounting the door panel for pivotal movement relative to the door frame.

Attached to each door frame channel web 5 and 7 for overlapping engagement with the adjacent peripheral face of the door panel is a door seal housing 9 comprised of a modified Z-shaped member having one flange 10 abutting the adjacent frame channel web 5 and provided with a slotted opening 11 through which extends a suitable fastening member 12. The outer end of flange 10 is offset at 13 for a purpose hereinafter discussed. The other end of flange 10 terminates in an outstanding web 14 which terminates in a flange 15 extending towards and terminating short of the adjacent face of the door panel 1. Confined by the adjacent frame channel Web 5, web 14 and flange 15 is a seal member 24 of cellular material having one face thereof abutting the face of the adjacent door panel and disposed across the inner end of the opening between the adjacent surfaces of the marginal edge of the door panel and the adjacent door frame channel web 5. Recessed into one face of member 24 is a sound transmitting member 24b, as hereinafter discussed. The adjustable mounting of Z-bar flange 10 permits placing member 16 under suflicient compression to insure full contact between the member 16 and the adjacent face of the door panel 1. Enclosing the above described as sembly is a cover plate 17 of general L-shape having a flange 17a underlying said offset 13 and a top surface attached to portion 15 by a suitable fastener 18. It will be understood each housing 9 and seal member 24 therein extends the full height or width of the adjacent door face and its end portions are suitably connected to provide in effect a continuous member about the entire periphery of the adjacent door panel face. The door panel 1 abuts the members 24 when in closed position and pivots away therefrom in opening.

The door seal housing overlying the threshold channel 6 of the door frame is preferably identical with the hereinbefore described housing 9, except that the member 17 is omitted and a threshold plate 19 is substituted therefor. Adjacent the door panel, plate 19 is supported by suitable members 20 disposed in suitable spaced relation longitu dinally of the threshold plate 19. The outer end of plate 19 is preferably provided with a depending flange portion 21 engaging the floor and the plate 19 is secured in position by suitable fasteners 22 securing the member 19 to the underlying door frame member 6.

Referring now to FIG. 4 of the drawing wherein is shown in cross-section the door seal member 16, such member is preferably rectangular in cross-section and extends the length of the housing 9 within which it is mounted, such member is of closed cell cellular rubber, foamed plastic or similar material. Referring now to FIG. 5 of the drawing wherein is shown a preferred form of seal member 24. Member 24 is comprised of a major portion 24a of cellular material, such as rubber or foamed plastic and preferably of the closed cell type. Member 24 has an insert 24b extending the length thereof and comprised of a fibrous or other form of sound transmitting material, preferably felt. As a preferred construction the felt is adhesively secured to the cellular body. Insert 24b engages the adjacent face of the door panel and extends across the clearance opening between the spaced confronting surfaces of the door panel and the door frame as indicated by the dot and dash line showing portions 14, 15. By way of example, and not limitation, commercially available materials such as Chemfoam SNC Soft closed cell cellular plastic may be employed in the body 24a of the seal 24 and spring felt 124XH may be employed in the insert 24b.

Sound seals as herein discussed are primarily for restriction of air borne sounds passing through the clearance openings between the movable door panel and the supporting door frame. As shown in the drawing, such clearance may be about /8 inch at three marginal edges of the door panel and at the latch side of the panel may increase to about inch at the inner face of the panel, by reason of the tapering marginal edge of the panel.

As discussed in the copending Wehe, Jr. application, the sound frequencies between 125 c.p.s. and 1400 c.p.s. are normally of principal consideration. However, sound frequencies between 1400 c.p.s. and 4000 c.p.s. may also be present. Due to the door thickness a substantial area is provided by the panel clearances within which sound may accumulate and must be restricted by the sound seal. Sound frequencies measured in cycles per second represent energy which must be either absorbed or transmitted by the sealing members 16 and 24 of the door seal. In the case of the seal member 16, by reason of its closed cell construction, the aforesaid energy must be absorbed and dissipated as heat. However, the sound pressure build up in the panel clearances does tend to force sound through seal member 16. In the case of the sound seal member 24, which has been found more effective than member 16, it appears that the low resistance of the felt insert 24!) to passage of sound prevents build up of sound pressure within the panel clearance spaces and permts continuous accumulation and dissipation of the sound as heat by body portion 24a. This is the present theoretical explanation of the superiority of seal member 24 over seal member 16.

Laboratory test comparing the same door panel and frame equipped with a magnetic type door seal as in copending Herbert W. Wehe, Jr. application Serial No. 286,289, with the door seal employing seal member 16 and the seal member 24 of the present application showed an A.S.T.M. Sound Transmission class No. of 45 when equipped with a magnetic type seal member, S.T.C. No. 46 when equipped with seal member 16 and an S.T.C. No. of 51 when equipped with the seal member 24. In other words, the seal member 16 showed a superiority of one decibel over the magnetic seal member, but seal member 24 showed a superiority of six decibels over the magnetic seal member. Under the S.T.C. rating provided by the A.S.T.M. test procedures, a three decibel rise in sound transmission loss represents an increase of 100% in the efficiency of the panel and seal assembly to attenuate sound passing therethrough.

It will be understood, by those skilled in the art, that any details of construction given here are for purposes of illustration and not limitation. The details of the housing for the door seal member may also be varied without departing from the spirit of the invention. The sound seal members 16 and 24 may also vary as to dimensional shape of the cellular body portion and I do not intend to be limited to the exact construction shown or materials identified, except as made necessary by the scope of the appended claims.

I claim:

1. A sound seal for restricting passage of air borne sound through the peripheral clearance openings between a door panel and the frame within which the panel is pivotally mounted, comprising,

(a) a seal housing portion extending longitudinally of and in spaced relation to each marginal edge of one face of the door panel and connected with the adjacent door frame surfaces providing a substantially continuous housing member,

(b) sealing means mounted within and extending longitudinally of each said housing portions and extending outwardly therefrom to engage a portion of the adjacent face of the door panel and to extend across the clearance openings between the peripheral margin of the panel and the adjacent frame surfaces,

(c) said sealing means comprising a resilient closed cell cellular sound absorbing body portion having a longitudinally co-extensive insert of a sound transmitting material which insert is juxtaposed to the clearance opening, said insert being bounded on at least two sides thereof by the cellular body portion, and

((1) means on each said housing portions for adjustably maintaining contact between said outwardly extending portion of the sealing means and the face of the adjacent panel surface.

2. A sound seal for restricting passage of air borne sound through the peripheral clearance openings between a door panel and the adjacent surfaces of the door frame within which the said panel is pivotally mounted, comprising,

(a) a member mounted upon each of the said frame surfaces and having an open substantially L-shaped portion overlying and extending longitudinally of the adjacent peripheral surfaces of said door panel and of the clearance'opening between the marginal edges of said panel and the adjacent door frame surfaces,

(b) a cover plate of substantially J-shape enclosing said member, with one edge of the cover plate connected with one edge of the sad member and the opposite cover plate edge overlying and secured to the other edge of the said member in spaced relation to the door panel,

(c) a sound seal disposed within said open L-shaped portion of said member and comprising a resilient closed cell cellular body portion having a longitudinally co-extensive insert of sound transmitting material which insert is juxtaposed to the clearance opening between the peripheral edge of the panel and the adjacent surface of the said frame, said insert being bounded on at least two sides thereof by the cellular body portion, and

((1) means connecting said member with the adjacent surface of the door frame for adjusting said member and sound seal therein to provide a bearing engagement between the face of the sound seal and insert with the adjacent door panel and frame surface, when the panel is in closed position.

References Cited by the Examiner UNITED STATES PATENTS 653,368 7/1900 Tschieky 20-69 1,581,811 4/1926 Rubin 20-69 2,078,207 4/1937 Page et al. 20-35 2,087,821 7/ 1937 Simpson 20-69 X 2,121,827 6/1938 Roberts 20-69 2,406,942 9/ 1946 Buttner. 2,922,202 1/1960 Kodaras. 2,954,591 10/1960 Miles 20-69 3,029,481 4/1962 Henniges 2069 3,039,156 6/1962 Morris et al. 20-69 3,041,681 7/1962 Goodwin 20-69 3,051,260 8/1962 Eckel 20-35 3,079,653 3/1963 Cornell 20-69 FOREIGN PATENTS 491,963 4/1953 Canada. 1,123,597 9/1956 France.

509,619 7/ 1939 Great Britain.

HARRISON R. MOSELEY, Primary Examiner.

REINALDO R. MACHADO, Examiner. 

1. A SOUND SEAL FOR RESTRICTING PASSAGE OF AIR BORNE SOUND THROUGH THE PERIPHERAL CLEARANCE OPENINGS BETWEEN A DOOR PANEL AND THE FRAME WITHIN WHICH THE PANEL IS PIVOTALLY MOUNTED, COMPRISING, (A) A SEAL HOUSING PORTION EXTENDING LONGITUDINALLY OF AND IN SPACED RELATION TO EACH MARGINAL EDGE OF ONE FACE OF THE DOOR PANEL AND CONNECTED WITH THE ADJACENT DOOR FRAME SURFACES PROVIDING A SUBSTANTIALLY CONTINUOUS HOUSING MEMBER, (B) SEALING MEANS MOUNTED WITHIN AND EXTENDING LONGITUDINALLY OF EACH SAID HOUSING PORTIONS AND EXTENDING OUTWARDLY THEREFROM TO ENGAGE A PORTION OF THE ADJACENT FACE OF THE DOOR PANEL AND TO EXTEND ACROSS THE CLEARANCE OPENINGS BETWEEN THE PERIPHERAL MARGIN OF THE PANEL AND THE ADJACENT FRAME SURFACES, (C) SAID SEALING MEANS COMPRISING A RESILIENT CLOSED CELL CELLULAR SOUND ABSORBING BODY PORTION HAVING A LONGITUDINALLY CO-EXTENSIVE INSERT OF A SOUND TRANSMITTING MATERIAL WHICH INSERT IS JUXTAPOSED TO THE CLEARANCE OPENING, SAID INSERT BEING BOUNDED ON AT LEAST TWO SIDES THEREOF BY THE CELLULAR BODY PORTION, AND (D) MEANS ON EACH SAID HOUSING PORTIONS FOR ADJUSTABLY MAINTAINING CONTACT BETWEEN SAID OUTWARDLY EXTENDING PORTION OF THE SEALING MEANS AND THE FACE OF THE ADJACENT PANEL SURFACE. 